Chapter 1: C&G

Biology

The study of life/living things.

Science

An active, empirical search for understanding the natural world.

Empirical

Based on observations or experiment, data-driven.

Shared characteristics of life

Cell(s), Metabolism, Reproduction, Growth/Development, Environment.

Viruses

False; viruses are not considered alive.

Main source of energy for life

Solar fusion.

Percent of Earth's energy from solar fusion

99.97%.

Chemistry of elements

An element is a substance that cannot be broken by chemical reactions.

Compounds

Substances formed when one element is combined with another, exhibiting emergent properties.

Major components of the human body

Oxygen, Carbon, Hydrogen, Nitrogen.

Trace element example

Iodine.

Natural source of iodine

Seafood.

Importance of iodine

Without iodine, a patient can develop goiter.

Goiter

Enlargement of the thyroid gland that produces hormones T3 and T4.

Symptoms of goiter

Red, puffy, and bulging eyes.

Thyroid function

Pumps a protein called thyroid globin and iodine; helps regulate metabolism.

Subatomic particles

Proton (positively charged), Neutron (neutrally charged), Electron (negatively charged).

Components of the nucleus

Protons and neutrons.

Atomic number particles

Just protons.

Atomic mass particles

Protons and neutrons.

Isotopes

Atoms with the same atomic number but different atomic mass.

Beta-minus decay

The release of an electron, resulting in an increase in atomic number.

PET Scan

Positron Emission Tomography, used to detect positrons released during beta-plus decay.

What does FDG stand for?

Fluorodeoxyglucose.

Use of FDG

Commonly used for detecting cancer in tumors.

Valence electrons

Electrons in the outermost shell of an atom.

Covalent bonding

The strongest bond formed by sharing electrons.

Electronegativity

The tendency of an atom to attract electrons; increases up a group and decreases across a period.

Polarity

Occurs when there is unequal sharing of electrons resulting in slight charges.

Ionic bonding

The transfer of electrons resulting in charged ions (cations and anions).

Hydrogen bonding

Weak bonds between polar molecules, involving slightly positive and slightly negative regions.

Van der Waals interactions

Random movements of electrons causing small charges in nonpolar molecules.